The Physical Function and Biomechanics (PFB) Core will provide a suite of tools to aid in characterizing functional and biomechanical phenotypes of low back pain. The tools provided by our team span sensing modalities ranging from full body motion tracking, high fidelity spine tracking, and unobtrusive activity monitoring. These methods are scalable for patient use, are validated against gold-standard methods, and have been deemed influential within the field of spinal health. These tools have demonstrated potential to predict back pain risk, assess function throughout recovery, and provide objective outcomes in relation to physical function and biomechanics. In addition, the PFB Core incorporates a technology evolution plan that will optimize our tools in response to key functional and biomechanical phenotypes identified from preliminary results from the UCSF REACH Research Project. We also propose developing a method to assess functional and biomechanical phenotypes from patient activity outside of the clinic using sensors and real-world data. Services from the PFB Core will provide the necessary study design input, hardware/devices, post-processing analyses, and data interpretation to deliver outcomes data to both UCSF REACH and the greater BACPAC Consortium. The PFB Core will support research spanning the bench-to-bedside continuum, providing unique tools in biomechanical motion and functional evaluation, and encouraging collaborations between basic, translational, and clinical researchers. Through this approach, we will address both fundamental questions and translational projects that cultivate a more integrated model of back pain, further our understanding of disease pathways and the basis for response to treatments and improve targeting of effective therapies and interventions to individual patients.